Fire-escape



(Noll/Lodel.)

s. H. ROPBR.

FIRE ESCAPE.

No. 516,116. Platented Mar. 6, 1894:.

WITNEEEEE: INVENTDR:

HE NATIONAL LWHGBHAPHINQ OGMPN wxsumqwn. an. y

. Nrrnn STATES ATEq ma,

SYLVESTER H. ROPER, OF BOSTON, MASSACHUSETTS.

FlREnESCAPE.

SPEGIFCATION forming part of Letters Patent No. 516,116, dated March 6, 1894.

Application led May 19, 1893.

Serial No. 474.762. (No model.)

.To aZZ whom t may concern,.-

Beit known that I, SYLvnsrnn H. Borna, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Fire-Escapes, of which the following is a specification.

This invention relates to that class of tireescapes in which an object or person is low ered by means of a line which unvvinds from a reel or drum.

An apparatus embodying these features is shown in my former patent, No. 439,191, granted October 28, 1890, and means are there illustrated whereby a suitable duid may be employed as a retarding agent to prevent too rapid rotation of the reel or drum in un- Winding.

The object of the present invention is to provide improved means for securing this retarding effect through the agency of a fluid.

To this end, the invention may be said to consist in combining with the reel or drum a cylinder arranged to rotate therewith and adapted to contain the fluid, a piston in said cylinder, means whereby the rotary motion of the cylinder is converted into reciprocating motion of the piston endwise of the cyl inder, and a restricted passage affording co mmunication from one side of the piston to the other.

The invention also consists in certain novel features of construction and combinations of parts hereinafter described and claimed.

The accompanying drawings illustrate a construction by which the invention may beL carried out.

Figure l shows a side elevation of the com plete apparatus, the suspending chain being broken, and the in ner and outer convolutions 'of the line or tape being indicated in broken lines. Fig. 2 shows a section on line 2-2 of Fig. l. Fig. shows a section on line 3-3 of Fig. 2. Fig. Il shows .a detail perspective view of a portion of the cylinder represented as broken away. Fig. 5 shows a detail of the piston.

The same letters of reference indicate the in all the figures.

In the drawings: The letter a designates a casing, which is adapted to be suspended from a suitable fixed support, as a sill, by means of a chain a attached to it and having a hook a2 at its free end. Thus the said casin g will be held practically stationary. spindle b extends through the said casing, and a drum or reel b is mounted on said spindle. A line, preferably a steel tape c, is attached to the drum, and Winds on the same Within vthe casing, the latter having an opening in one side through which the tape issues from the case. An extension b2 of the spindle b projects from one side of the casing, and a cylinder or chamber b3 surrounds said extension and is fast with the drum o', being preferably formed integral therewith. A shoulder b4 is formed between the drum and cylinder, and a plate a3 fits around the drum and against the shoulder and forms one side of the casing, said plate being preferably fast With the drum, so that it turns therewith. A shoulder b5 is preferably formed between the spindle and the extension thereof, and tits against the inner end of the cylinder b3. The outer end ofthe cylinder is closed by a head 1J, which is fastened on by screws o7, and bears against the outer end of the spindle extension b2. The spindle extension andthe cylinder are concentric, and a piston d is fitted on said eX- tension and is adapted to reciprocate in the cylinder. Reciprocations of the piston are brought about through the rotation of the cylinder, and the means here shown for eecting this conversion of motion consist in a camgroove e encircling the piston, and a pin e set in the cylinder and engaging said groove. The piston is splined to the spindle-extension by means of a feather e2, so that rotation of these parts independent of each other is prevented, and the piston is properly guided. A restricted passage adords communication from one side of the piston to the other, and in the present instance this passage, which is designated f, extends through the spindle-extension b2, entering one side of the same at the inner end of the cylinder, and thence extending longitudinally of said spindle-extension to the outer end thereof, the restriction being effected by means of small grooves f in the end face of the spindle-extension and radiating from the passage f. A set-screw g, inserted in the cylinder-head ZJ, has its end in the passage f, and affords means for regulating the amount of restriction.

The cylinder bs is filled with fluid, prefer- ICO ably glycerine on account of its density, andy the operation is as follows: The' apparatus being suspended yfrom a rigid support,y the object or person to belowered is attached yto the tape c, the latter being provided at its end with suitable means such as a band e', to facilitate the attachment, and the weight of such y object or person unwinds the tape from the drum which revolves on the spindle b. The cylinder b3 being fast With the drunnfit is likewise revolved, and itsy revolution causes the piston d to be reciprocated through the means through the restricted passage f, and the restriction of said passage' p'roduce's'a resistance f to the piston and consequently to the rotation of the cylinder and drum. It is evident the'tape' can unwind only in a ylimited degree of speed, and hence an object or person may y' be' lowered with perfect safety. Provision is made for re-winding ythe tape whiley the resistance is dormant, as follows: The spindle projects from the case (1 as ata/3 andr a ratchet h is afIiXed to it, inthe present instance by flattening two sides of the spindle and correspondingly shaping ythe opening iny the ratchet which receives the spindle, and by screwinga nut hfon the end ofy the spindle,

which is threaded for the purpose, and clamping the ratchet between it and a shoulder h2y of the spindle. The ratchet Works close to the case, anda payvl h3 is pivoted' to the'lat ter and ypressed into engagement with the ratchet by a springht The direction of rotation of the drum during the unwinding of the tape is such that the pawl h3 forms a stop, which prevents rotation of the ratchet and consequently of the spindle, and hence the drum turns on the spindle and reciprocating motion is imparted to the piston, as before described. When the drum is rotated in the reverse direction, however, the pawl no longer acts as a stop, and the ratchet may freely pass it. Hence the drum and spindle move together during rotation in this latter direction, and the cylinder and spindle-extension being fast with the drum and spindle respectively, they also move together and carry the piston with them, so that no reciprocation of the latter takes place, and hence the resistance is absent. The tape may be rewound by means of a crank c', adapted to be screwed into a threaded hole i in the edge of the cylindenhead h6. When not in use, this crank may be conveniently carried in a holder j fastened to the case a.

It is evident that numerous changes might be made in the construction here shown, without departing from the spirit of the in# vention. The restricted passage by which communication is afforded from one side of ythe piston to the other might bey by other channels than those here illustrated. For example, the pistou could have a loose fit, which would permit passage ofthe duid. yThe structure is susceptible of many variations, and yhence the invention isnot limited to the specific means by which I have here chosen to illustrate it.

Having thus described my invention, whatr I claim as new, and desire to secure by Letters l. A fire-escape, comprising in its construcf tiona rotatable drum suitably supported, a

yline attachedy to said drum, a cylinder arranged to rotate with the drum, a piston iny the cylinder, means for converting rotary motion of the cylinder into reciprocal motion of the piston endwise of the cylinder, and a" restricted passage affording communication from one side of the piston'to the'other. y

2. A fire-escape, comprising in its construc-y tion a rotatable drum suitably supported, a

'line attached' to said drum, a cylindery arranged to rotate with the drum, a piston in the cylinder, means foraconvert-ing rotary motion of the cylinder intoy reciprocal motiony of piston endwise of the cylinder, suchy means consisting of a cam-groove in one part and a yprojection on the yother part engaging said groove, and a restricted passage affordingV communication from one side yof the piston to the other. f 3. A fire-escape, comprising in its constructionfa spindle and support therefor, a'drum f on said spindle, a line attached to said drum,

f a cylinder arranged to rotate with the drum TOO and ,surroundingan extension of the spindle,

a piston in the cylinderand around the spindle, a restricted passage extending through the spindle and affording communication from one side of the piston to the other, and means for converting rotary motion of the cylinder into reciprocating motion of the piston.

4. A fire-escape, comprising in its construction a spindle and support therefor, a drum on said spindle, aline attached to said drum, a cylinder arranged to rotate with said drum,

IIO

a piston in said cylinder,arestricted passage l affording communication from one side of the piston to the other, means for converting rotary motion of the cylinder into reciprocal motion of the piston, a ratchet on the spindle,

' and a pawl on the spindle-support and engaging said ratchet.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

SYLVESTER H. ROPER. Witnesses:

C. F. BROWN, A. W. HARRISON. 

